house foundation has no insulation - how bad is it?

[drunat]

Hi. We are in the process of buying an unfinished house. Not much left to finish - flooring and heating system. However it appears that house insulation is fairly poor. We did pyrite testing today and the guys discovered that there is no insulation in the concrete at all i.e. there is about 9 inches concrete and infill underneath - nothing in between. How bad is it? Is this house a loss cause with such foundation? Anything we can do now, for example put insulation on top of concrete and then flooring? I assume this will reduce the ceiling high somewhat. On top of that the house is built of concrete blocks (possibly hollow?) and there is only 40 mm styro foam insulation and standard plaster board. I believe this is also below current requirements (of 100mm) so any opinion on how bad this insulation is is welcome. We don't really have a budget for external insulation. Will it be a very cold house then that would be impossible to keep heat in?

 

[Padraigb]

I get the impression that you do not know much about building. You should not have insulation material in foundations; there is a case for having some in the subfloors, but it is not necessarily a disaster if there isn't any.

Get a building surveyor in. It's money well spent, especially if you are not reasonably expert in the field.

 

[drunat]

Yes I know absolutely nothing about building - only what I am told. Got structural engineer in already - he did not open anything up and could not comment on wall or floor insulation. Had plumbers in yesterday who noticed the wall insulation low - a bit disappointed with the engineer that he did not point it out as it is fairly obvious - there are areas in the wall that are open (around plumbing connections) where insulation can be see. Re. floor insulation - the guys who did pyrite testing said that there is no insulation and that there should be ne between the infill and the concrete - may be they meant dump membrane? Basically there is nothing between the infill and concrete. We have not bought the house yet just have a deposit and already spent a fortune on planning investigations, engineer etc so I am looking for free opinions here if you wish Pyrate tests might yet to turn positive so not going to spend any more money until we get the results of the test. Any opinions re. insulation questions welcome. Thanks. Just to add - it's a self built house and the builder is in a receivership so there are no guarantees and no come back on anything after/if we buy it.

 

[Padraigb]

It sounds as if your engineer did not do much to earn his or her fee!

1. You need a damp-proof membrane (which can be heavy-gauge plastic sheet) under your subfloors. I'd be concerned if that was absent. A layer of insulating material is also good, but almost all the heat that goes into concrete flooring comes back into the house eventually. That's why I say the absence of insulation is not necessarily a disaster.

2. It is important to ascertain if the house is built with cavity blocks, or if it has a cavity wall (essentially, a double wall with a gap between the two leaves). You can not reasonably put insulation in cavity blocks, and in my opinion they are quite inferior to cavity walls. The insulation in cavity walls can be provided either by air or a manufactured insulating material, or both (both can be achieved by having a 100mm cavity with 40mm styrofoam and 60mm air).

3. Gaps in the wall are an annoyance, but can (and should) be rectified at very little cost. I presume the only plumbing going through the external wall is outlet or waste pipes; I wouldn't like anything else there.

Given what you are considering taking on, it might be worth investing in a book on the basics of building, and doing some intense reading.

 

[lowCO2design]

that is unbelievable that a house recently built would not have have any floor insulation and how it could conceivably be built with hollow block and 40mm wall insulation is beyond me.
just to clarify a few things:

• dont be annoyed at your engineer - engineers deal with structure - you need an architect (who is also a BER assessor) to deal with your insulation queries.
• 100mm is not necessarily compliant with building regulation. there is now a requirement to carry-out a BER assessment to ascertain insulation levels etc.
• ask yourself this- if this builder didn't put in something as basic as floor insulation - do you really want to buy this house? do you really??
• you state that the there is no guarentees as the builder is bust. Run, run a mile, as from what you've explained here. this guy was NO builder to begin with..

It sounds as if your engineer did not do much to earn his or her fee!

why do you say that

1. You need a damp-proof membrane (which can be heavy-gauge plastic sheet) under your subfloors. I'd be concerned if that was absent. A layer of insulating material is also good, but almost all the heat that goes into concrete flooring comes back into the house eventually. That's why I say the absence of insulation is not necessarily a disaster.

I strongly disagree. lets recap on what your saying here. there is NO DPC so the every junction of floor and wall will need invasive remedial works or an electro osmosis system (in a new house!) AND NO thats riduclous to suggest that

almost all the heat that goes into concrete flooring comes back into the house eventually.

ridiculous

2. It is important to ascertain if the house is built with cavity blocks, or if it has a cavity wall (essentially, a double wall with a gap between the two leaves). You can not reasonably put insulation in cavity blocks, and in my opinion they are quite inferior to cavity walls.

agreed but then you go on to say

The insulation in cavity walls can be provided either by air or a manufactured insulating material, or both (both can be achieved by having a 100mm cavity with 40mm styrofoam and 60mm air).

insulation in a block built cavity CAN NOT be provide by AIR!! thats a mental misleading statement to make. current cavity wall are generall 150mm fill full bond bead and can be wider 200-300mm

3. Gaps in the wall are an annoyance, but can (and should) be rectified at very little cost.

air-tightness is now generally considered as important as insulation. the OP will need more than a book to rectify this property IMHO

Yes I know absolutely nothing about building - only what I am told. Got structural engineer in already - he did not open anything up and could not comment on wall or floor insulation. Had plumbers in yesterday who noticed the wall insulation low - a bit disappointed with the engineer that he did not point it out as it is fairly obvious - there are areas in the wall that are open (around plumbing connections) where insulation can be see.

this is not generally an eng's remit

Re. floor insulation - the guys who did pyrite testing said that there is no insulation and that there should be ne between the infill and the concrete - may be they meant dump membrane? Basically there is nothing between the infill and concrete.

in many new builds, I try to express the need for good insulation levels, reduce any thermal bridges and achieving high levels of air-tightness etc,. here you dont even have a RADON BARRIER & SUMP! IMHO walk away

We have not bought the house yet just have a deposit and already spent a fortune on planning investigations, engineer etc so I am looking for free opinions here if you wish Pyrate tests might yet to turn positive so not going to spend any more money until we get the results of the test. Any opinions re. insulation questions welcome.

if you cant afford external wall insulation then you cant begin BEGIN to bring this property upto current building regulations

there is no insulation in the concrete at all i.e. there is about 9 inches concrete and infill underneath - nothing in between. How bad is it?

fundamental in that your builders cannot be trusted. modern houses are now putting at least 100mm if not 200mm in the floor

Is this house a loss cause with such foundation?

IMHO yes, unless your buying it for the site

Anything we can do now, for example put insulation on top of concrete and then flooring? I assume this will reduce the ceiling high somewhat.

min ceiling height should be 2.4 meters or 8ft

On top of that the house is built of concrete blocks (possibly hollow?)

RUN away

and there is only 40 mm styro foam insulation and standard plaster board.

run run away

I believe this is also below current requirements (of 100mm)

generally its more than this, and drylining to that thickness is no longer considered good practice

so any opinion on how bad this insulation is is welcome. We don't really have a budget for external insulation. Will it be a very cold house then that would be impossible to keep heat in?

from what you have stated above YES. who is going to certify that it complys with building regs? and are you sure the bank will lend for such a substandard house?

 

[Superman]

As lowCO2 says, RUN AWAY and be thankful you did.

If the builder didn't put in floor insulation, there will be nothing right in that house.

 

[Leo]

Good post LowCO2, and I can only agree, under no circumstances should you consider buying that house! You will only regret it for years to come.

You may already have spent considerable money investigating it, but put that down as money well spent in avoiding having to pay huge money attempting to rectify a house that will never meet modern building standards and will cost you a fortune to heat into the future.

 

[terrysgirl33]

An uncle-in-law built a house with no underfloor insulation in the 80's, it is a cold and miserable house. Our house was built with sheets of insulation under the concrete in the floor, in 1998. I don't know much about building, but it was a 3 bed semi-d in a houseing estate, so underfloor insulation would be pretty basic thern if they put it in.

 

[drunat]

Thanks very much everyone for replies.

from what you have stated above YES. who is going to certify that it complys with building regs? and are you sure the bank will lend for such a substandard house?

We got a compliance with building regulations letter and completion letter from the architect who was involved in building the house. The leter states though that he did not oversee every part of the build so not responsible for work covered up. Banks seems to be happy. Clearly the letter is just a fiddle and done up just so the house can be sold.
At this stage we understand that it is a bad buy as is. Also the guys who did the pyrite test said that it looks like there is actually pyrite in the fill as it was shiny when they took it out - it is yet to be confirmed by the lab.
The thing is that we really liked the house and the location and site is great and suits us down to the ground. So my question now is if we were to get a really really good price i.e. essentially paying for the site, we then could deal with Pyrite/insulation issue by taking out concrete, infill etc and putting in proper foundation - I know very expensive but we will be budgeting for it. How would we then deal with wall insulation? Is external insulation our only option? Or since the house will be in a mess anyway, should we just remove plaster boards and put in more insulation internally? Is it doable? Does it make sense? Does it make sense to try and insulate the walls or is it the case that we might as well knock the house down and build it from scratch again (very extreme I know but just brain storming here ?

 

[PaddyBloggit]

Why make trouble for yourselves?

You've got very good advice here ... forget trying to remedy the site .... it will be a money pit ... consider yourselves lucky and walk away from it now.

Do more than walk .... as advised above .... RUN, RUN and keep running.

 

[Leo]

Is it doable?

Yes.

Does it make sense?

No.

Does it make sense to try and insulate the walls or is it the case that we might as well knock the house down and build it from scratch again (very extreme I know but just brain storming here ?

It's very extreme. The best approach would be to knock the entire structure, remove all trace of the infil (if it is affected by pyrite), and start from scratch. That would not be cheap!

 

[Superman]

Price it on the basis that it is a site, where Planning Permission will be granted, but include for the cost and time in demolishing and removing the existing house.
You almost certainly need to demolish the existing house. You need to get a competent professional on board to discuss options.

Frankly, I would walk away.

 

[lowCO2design]

We got a compliance with building regulations letter and completion letter from the architect who was involved in building the house. The leter states though that he did not oversee every part of the build so not responsible for work covered up. Banks seems to be happy. Clearly the letter is just a fiddle and done up just so the house can be sold.

the fiddle is by the seller/ developer/ builder. the architect has just provided an opinion on complaince - s/he has no remit in written such a cert to open-up floors or walls..

At this stage we understand that it is a bad buy as is.

how much are we taking? can you justify this purchase based on the site alone?

Also the guys who did the pyrite test said that it looks like there is actually pyrite in the fill as it was shiny when they took it out - it is yet to be confirmed by the lab.

well that would be the nail in the cofin - you WOULD BE KNOCKING IT, forget renovating of a floor if there's pyrite. think about the foundations! I live in Cork City and there is huge issues with subsidence. this cost major bucks, I mean you could be talking 50g easy. and that's not counting the floors you may have to lift..

The thing is that we really liked the house and the location and site is great and suits us down to the ground.

so bring all your correlated evidence to the sellers representative and tell them 'this house needs to be knocked! but I'm interested in buying the site, how much?'

So my question now is if we were to get a really really good price i.e. essentially paying for the site, we then could deal with Pyrite/insulation issue by taking out concrete, infill etc and putting in proper foundation - I know very expensive but we will be budgeting for it.

you can budget for that and not EWI, I'm starting to think, your having a laugh here, and wasting our time..

How would we then deal with wall insulation?

tell us where in the country you are and someone will recommend a good architect/technologist to consult on your disaster area

Is external insulation our only option?

no but given what you've told us above, It would be my preferred one

Or since the house will be in a mess anyway, should we just remove plaster boards and put in more insulation internally?

not adviseable and not good practice

Is it doable?

yee, sure why not, the rest of your potential house is so .... what will a bit of condenstion, mould, and few more carcinogen's do to you..

Does it make sense?

no, this thread stopped making sense when you said there was no insulation in the concrete floor

Does it make sense to try and insulate the walls or is it the case that we might as well knock the house down and build it from scratch again

there you go..

 

[lowCO2design]

just an aside note/question - what are the potential legal ramifications of the OP (or any person in a similar situation) making such reports (evidence of non-compliance with building regulations) on such a property to the public attention - ie to save similar persons having to fork out for their own consultant reports or worse not cop it till they've moved in..

 

[Guns N Roses]

The apparent lack of any insulation in the floor contruction would be a definate reason to walk away. Fixing it at this stage will cost you. Bear in mind that 30% of heating in a house is lose through uninsulated floors. It will be a cold house and will cost you a fortune to heating it.

Providing insulation under concrete floor slabs has been standard for many years now. Obviously the original builder doesn't know a lot about house contruction.

As other posters have advised you RUN FOREST RUN!

 

[drunat]

OK I hear you all - the house is a disaster!

you WOULD BE KNOCKING IT, forget renovating of a floor if there's pyrite. think about the foundations! I live in Cork City and there is huge issues with subsidence. this cost major bucks, I mean you could be talking 50g easy. and that's not counting the floors you may have to lift..

I know that it is pricey but if we get the house/site for the price of a site we would have the money to fix it.

So my question now is if we were to get a really really good price i.e. essentially paying for the site, we then could deal with Pyrite/insulation issue by taking out concrete, infill etc and putting in proper foundation - I know very expensive but we will be budgeting for it.
you can budget for that and not EWI, I'm starting to think, your having a laugh here, and wasting our time..

Not having a laugh a all - I asked this question on the basis that we get a better price i.e. significantly lower than what we have sale agreed now hence the new "available" funds.
OK I might give a bit of background here as to what kind of house it is and why we like it and still trying to see if there is anything at all that we could do to save it. - it is a 5 bed detached house approx. 2400 ft2 in D15, OK size garden, down a quiet lane - it's a one off house and it feels like you are in the country while being 2 minutes away from a train station which brings you to town in 20min. We have sale agreed at 280k. The house was built in 2007 and is unoccupied and unfinished since then. The insulation issue aside, the things that are unfinished - floors, heating system, kitchen, driveway. A separate reputable contractor did all electrics, we did CCTV sewage and it's OK. No moulding / dumpness anywhere. The house is sold through a receiver. We thought there was no way we could find a house of a similar calibre and a similar price in this location (we are on the lookout for a good while now). Now, this was our thinking before we found out about foundation/pyrite/insulation issues. We now have to go back to the vendor and withdraw our offer or put in another one. If we got this house/site for say 100k (very unlikely they'll sell it to us at that, instead will probably put in at an auction), we then would have money to fix it.
So, what I am trying to figure out here is whether or not it is fixable. I understand you do not have to demolish the house to redo the foundation? Those who suggest demolition, do you think that it is cheaper to demolish and rebuild than to redo foundation and fix the walls? Sorry, I do not mean to offend anyone with such simple questions, I am genuinely clueless

just an aside note/question - what are the potential legal ramifications of the OP (or any person in a similar situation) making such reports (evidence of non-compliance with building regulations) on such a property to the public attention - ie to save similar persons having to fork out for their own consultant reports or worse not cop it till they've moved in..

I was wondering so myself. If pyrite reports comes back positive I would be very tempted to put an address up there for all to see with the report attached. I fear the receiver might put the property up for an auction without disclosing all information and then someone else will be in trouble. It is my belief that a lot of dodgy houses are salt at auctions.

 

[Superman]

Those who suggest demolition, do you think that it is cheaper to demolish and rebuild than to redo foundation and fix the walls?

To get a compliant building, yes, it would be cheaper.
There is a reason for this.
You cannot fully know how bad the house is constructed at this stage. What you do know is that the builder makes fundamental mistakes. Noone can rely on that person.

Imagine you are buying a car that some person built by hand. It does not have a steering wheel. Do you think: "that's ok I'll buy it and put in my own steering wheel" or do you think "if this person was stupid enough to build a car and not put in a steering wheel, I'd hate to think what he would do with brakes."

 

[lowCO2design]

So, what I am trying to figure out here is whether or not it is fixable.............. I am genuinely clueless

you are on a public forum, and I cannot see the building in question. I have been as honest and frank as I can be, and can do no more. good luck with it